1. Field of the Invention
The present application relates to a method of making a dental product, in particular a dental bridge, in which a blank made of a pre-sintered green body is first machined and subsequently sintered to its final density.
2. Description of the Related Art
A known method of making dental prostheses includes pressing a ceramic powder into a green body that is subsequently subjected to a pre-sintering operation in which the green body becomes a somewhat more solid blank but does not reach its final density. A machining operation is performed on the blank in order to form a dental prosthesis and the so formed product is then sintered to its final density. United States patent application publication US 2004/01 19180 A1 discloses a method in which a pre-sintered blank is machined by a milling process and dense-sintered in a temperature range of from 1200 to 1650° C. According to US 2004/01 19180, the pre-sintered blank has a “green strength” of from 31 MPa to 50 MPa. It is further indicated that blanks having a strength that lies outside the chosen range of 31 to 50 MPa do not yield useful results. According to the publication in question, blanks having a strength below the indicated range may break during milling while higher strengths result in hard blanks that cannot be machined using customary machining processes. It is an object of the present application to provide an improved method of making dental prostheses as will be explained in the following.